Le Chatelier's Principle Lesson 2

Le Chatelier’s Principle If a system in equilibrium is subjected to a change processes occur that oppose the imposed change and the system shifts to reach a new state of equilibrium. ⇌ Chemists can use this principle to shift the reaction so that there are more Products or Reactants. products reactants

Le Chatelier’s Principle If a system in equilibrium is subjected to a change processes occur that oppose the imposed change and the system shifts to reach a new state of equilibrium. ⇌ Chemists can use this principle to shift the reaction so that there are more Products or Reactants. products reactants

Le Chatelier’s Principle If a system in equilibrium is subjected to a change processes occur that oppose the imposed change and the system shifts to reach a new state of equilibrium. ⇌ Chemists can use this principle to shift the reaction so that there are more products or Reactants. products reactants

1.1 Increasing the temperature always shifts a reaction in the direction that consumes energy. A + B ⇌ C + Energy

1.2 Increasing the temperature always shifts a reaction in the direction that consumes energy. A + B + Energy ⇌ C

1.3 Decreasing the temperature always shifts a reaction in the direction that produces energy. A + B + Energy ⇌ C

2.1 Adding a reactant or product shifts the reaction in the opposite direction. A + B ⇌ C + Energy stress- increase [A] reaction- shift right

2.2 Adding a reactant or product shifts the reaction in the opposite direction. A + B ⇌ C + Energy stress- increase [C] left

2.3 Removing a reactant or product shifts the reaction in the opposite direction. A + B ⇌ C + Energy stress- decrease [A] reaction- shift left

2.4 Removing a reactant or product shifts the reaction in the opposite direction. A + B ⇌ C + Energy stress- decrease [C] reaction- shift right

3.1Only changes to (aq) and (g) reactants or products cause the equilibrium to shift (s) and (l) do not! You can change the concentrations of (aq) and (g) (s) and (l) have constant concentrations CaCO 3(s) + 2H + (aq) + 2Cl - (aq) ⇌ Ca 2+ (aq) + 2Cl - (aq) + CO 2(g) + H 2 O (l)

3.1Only changes to (aq) and (g) reactants or products cause the equilibrium to shift (s) and (l) do not! You can change the concentrations of (aq) and (g) (s) and (l) have constant concentrations CaCO 3(s) + 2H + (aq) + 2Cl - (aq) ⇌ Ca 2+ (aq) + 2Cl - (aq) + CO 2(g) + H 2 O (l)

3.1Only changes to (aq) and (g) reactants or products cause the equilibrium to shift (s) and (l) do not! You can change the concentrations of (aq) and (g) (s) and (l) have constant concentrations CaCO 3(s) + 2H + (aq) + 2Cl - (aq) ⇌ Ca 2+ (aq) + 2Cl - (aq) + CO 2(g) + H 2 O (l) no shift!

3.2Only changes to (aq) and (g) reactants or products cause the equilibrium to shift (s) and (l) do not! You can change the concentrations of (aq) and (g) (s) and (l) have constant concentrations CaCO 3(s) + 2H + (aq) + 2Cl - (aq) ⇌ Ca 2+ (aq) + 2Cl - (aq) + CO 2(g) + H 2 O (l)

3.2Only changes to (aq) and (g) reactants or products cause the equilibrium to shift (s) and (l) do not! You can change the concentrations of (aq) and (g) (s) and (l) have constant concentrations CaCO 3(s) + 2H + (aq) + 2Cl - (aq) ⇌ Ca 2+ (aq) + 2Cl - (aq) + CO 2(g) + H 2 O (l) shifts to products

3.3Only changes to (aq) and (g) reactants or products cause the equilibrium to shift (s) and (l) do not! You can change the concentrations of (aq) and (g) (s) and (l) have constant concentrations CaCO 3(s) + 2H + (aq) + 2Cl - (aq) ⇌ Ca 2+ (aq) + 2Cl - (aq) + CO 2(g) + H 2 O (l)

3.3Only changes to (aq) and (g) reactants or products cause the equilibrium to shift (s) and (l) do not! You can change the concentrations of (aq) and (g) (s) and (l) have constant concentrations CaCO 3(s) + 2H + (aq) + 2Cl - (aq) ⇌ Ca 2+ (aq) + 2Cl - (aq) + CO 2(g) + H 2 O (l) shifts to products

3.4Only changes to (aq) and (g) reactants or products cause the equilibrium to shift (s) and (l) do not! You can change the concentrations of (aq) and (g) (s) and (l) have constant concentrations CaCO 3(s) + 2H + (aq) + 2Cl - (aq) ⇌ Ca 2+ (aq) + 2Cl - (aq) + CO 2(g) + H 2 O (l)

3.4Only changes to (aq) and (g) reactants or products cause the equilibrium to shift (s) and (l) do not! You can change the concentrations of (aq) and (g) (s) and (l) have constant concentrations CaCO 3(s) + 2H + (aq) + 2Cl - (aq) ⇌ Ca 2+ (aq) + 2Cl - (aq) + CO 2(g) + H 2 O (l) shifts to reactants

3.5Only changes to (aq) and (g) reactants or products cause the equilibrium to shift (s) and (l) do not! You can change the concentrations of (aq) and (g) (s) and (l) have constant concentrations CaCO 3(s) + 2H + (aq) + 2Cl - (aq) ⇌ Ca 2+ (aq) + 2Cl - (aq) + CO 2(g) + H 2 O (l)

3.5Only changes to (aq) and (g) reactants or products cause the equilibrium to shift (s) and (l) do not! You can change the concentrations of (aq) and (g) (s) and (l) have constant concentrations CaCO 3(s) + 2H + (aq) + 2Cl - (aq) ⇌ Ca 2+ (aq) + 2Cl - (aq) + CO 2(g) + H 2 O (l) shifts to products

3.6Only changes to (aq) and (g) reactants or products cause the equilibrium to shift (s) and (l) do not! You can change the concentrations of (aq) and (g) (s) and (l) have constant concentrations CaCO 3(s) + 2H + (aq) + 2Cl - (aq) ⇌ Ca 2+ (aq) + 2Cl - (aq) + CO 2(g) + H 2 O (l)

3.6Only changes to (aq) and (g) reactants or products cause the equilibrium to shift (s) and (l) do not! You can change the concentrations of (aq) and (g) (s) and (l) have constant concentrations CaCO 3(s) + 2H + (aq) + 2Cl - (aq) ⇌ Ca 2+ (aq) + 2Cl - (aq) + CO 2(g) + H 2 O (l) no shift- liquids have constant concentration-drop in the bucket syndrome!

4.1Adding a catalyst does not shift the equilibrium, however it does allow you to reach equilibrium faster and both the forward and reverse rates are increased by the same amount.

products reactants

4.1Adding a catalyst does not shift the equilibrium, however it does allow you to reach equilibrium faster and both the forward and reverse rates are increased by the same amount. products reactants products reactants

5.1 Adding an inert (non-reactive) gas does not shift the equilibrium. 2NH 3(g) ⇌ N 2(g) + 3H 2(g)

5.1 Adding an inert (non-reactive) gas does not shift the equilibrium. 2NH 3(g) ⇌ N 2(g) + 3H 2(g) Adding Ne (g)

5.1 Adding an inert (non-reactive) gas does not shift the equilibrium. 2NH 3(g) ⇌ N 2(g) + 3H 2(g) Adding Ne (g) No shift!